High
E16 on Saunier Duval Thema F 30 E Plus

Your boiler is still detecting a flame even though it has commanded the burner to shut down, which is a safety concern that prevents it from restarting.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Ionisation fault (flame detected after burner off)

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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